midnightzxt Posted October 2, 2007 Share Posted October 2, 2007 Has anyone tried using the Megalogviewer's VE analysis yet? I'm wondering how accurate it might be. Also, can anyone tell me if there a guide on tuning spark for the megasquirt? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 2, 2007 Share Posted October 2, 2007 MLV is very good at tuning and will sort out the VE maps in about two to three iterations if you give it a good AFR map. Spark timing...lots of spark timing maps are available on here in the EMS threads but they differ from engine to engine. I like to have full advance (35deg) by 3000 rpms and pull out about 1.5 - 2 degrees for every psi or so. I idle at 23-25deg and pull it really low in the starter cranking range. L28ET stock long block. 42# injectors. Quote Link to comment Share on other sites More sharing options...
datman Posted October 2, 2007 Share Posted October 2, 2007 I was wondering about the amount of delay I should use on the wideband when using ve analysis....from looking at the logs it seems there is about .4 to .5 sec delay so should I use 0 sec delay or 1 sec delay...does it make much difference? I think setting the advance settings should also help...ie minimum and max rpm range . Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted October 2, 2007 Share Posted October 2, 2007 i use it -but since i am a klutz with a computor it took me awhile to figure it out.i would assume that it takes your data log and compares it to your programed a/f map and generates your new corrected map.for a long time i just ran my ms with the auto-tune turned on and the innovate wide band as an input.but you can tell this wasnt working-the innovate a/f guage was hunting all over.and i ended up with engine damage.after building a new motor i decided it was time to learn more about tuning the ms.i run data logs on an old ibm laptop -it records them onto a floppy.then i pull the floppy run the datalog thru megalog viewer .its great to watch the fuel table numbers change while the program is doing its work.i am guessing that if the tables are very close you will see the a/f numbers on the innovate gauge hold more steady.when i do run datalogs i run unleaded race gas-the engine wont ping as easy on a lean mixture.i just installed a new cam (isky 7181) and now i have a part throttle lean spot and 3000 to 4000 rpm-the innovate gauge is mounted between the tach and speedo on double sided velcro tape.hopefully it will be time for a dyno run soon.the last cam generated a 92% duty cycle on 42lb/hr injectors-maybe bigger injectors are coming.my goal would is 350rwhp on 91 pump premium with out pinging-but i think the n42 head is causing problems-c/r os calculated to be 8.3/1 Quote Link to comment Share on other sites More sharing options...
midnightzxt Posted October 2, 2007 Author Share Posted October 2, 2007 MLV is very good at tuning and will sort out the VE maps in about two to three iterations if you give it a good AFR map. Spark timing...lots of spark timing maps are available on here in the EMS threads but they differ from engine to engine. I like to have full advance (35deg) by 3000 rpms and pull out about 1.5 - 2 degrees for every psi or so. I idle at 23-25deg and pull it really low in the starter cranking range. L28ET stock long block. 42# injectors. Can you post up a jpeg of your afr table so that I can review it?I have a good idea of how everything from 2800 and right should look, but what afrs should I put on the left side of the table (low rpms and high kpa) Quote Link to comment Share on other sites More sharing options...
midnightzxt Posted October 2, 2007 Author Share Posted October 2, 2007 Here is what my afr table looks like right now.. any suggestions? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 2, 2007 Share Posted October 2, 2007 My current msq file is here: http://forums.hybridz.org/showthread.php?t=126101 TUNING TIP OF THE DAY: Whenever you use any auto tune or VE analyzer, go back to the tuning map and review it for big bumps and valleys before you drive on it. Sometimes the computer will go waaay low or high with a few datapoints. Just level them out manually in the 3D tuning grid before you drive it. My motor just about falls flat on anything leaner than 14.5:1 Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 2, 2007 Share Posted October 2, 2007 Just a heads up on the delay setting: open up a log and look for an event where the throttle goes from 0 to 100 (or something close). Then look for how much later you see the AFR change. On my NA at low revs the delay is 7 cycles. I believe this is because I have my O2 sensor installed past the header's collector all the way down in the main pipe. I did this because my header is ceramic coated and I didn't want to drill through it. But the max setting for delay on megalogviewer is only 4, so there is some error. I mostly see it at low revs and low MAP levels where it recommneds much higher VE values than are actually needed. I've been meaning to post a question on the MS forum to see if there is a work around to increase the delay up to 7, but haven't gotten around to it yet. Anyone here dealt with this? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 2, 2007 Share Posted October 2, 2007 Maybe I havent seen an issue with this because my WBO2 is about 3 inches after the turbine exit. Quote Link to comment Share on other sites More sharing options...
midnightzxt Posted October 2, 2007 Author Share Posted October 2, 2007 What MS are you running? I'm trying to understand why your afr table is 12x12 and mine is 8x8. Is that a embedded code issue? (I'm running 021s and going to upgrade soon) Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted October 2, 2007 Share Posted October 2, 2007 Ms-ii Quote Link to comment Share on other sites More sharing options...
datman Posted October 2, 2007 Share Posted October 2, 2007 So on the wideband delay does 1 represent 1 cycle? i thought it was 1 second. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 2, 2007 Share Posted October 2, 2007 I believe the delay is measured in cycles (not seconds) and each cycle is ~100 msec (1/10 of a second). Quote Link to comment Share on other sites More sharing options...
datman Posted October 2, 2007 Share Posted October 2, 2007 Ah right, that makes more sense...I will try that and see what happens. Thanks Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 4, 2007 Share Posted October 4, 2007 http://msefi.com/viewtopic.php?t=26021 I was going to post a question and found that the author had already discussed it. Since I'm seeing a delay of 7 at low rpms and low map, I think I'll try his suggestion to do 2 passes. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted October 9, 2007 Share Posted October 9, 2007 I was a bit off in how I was reading the delay in megalogviewer. The correct way is to drive with a light steady throttle and then nail it to WOT. Then go look at the log and count how many cycles there are between opening the throttle all the way and the AFR changing. For me it turns out to be 2-3 cycles. Previously I was looking at how long it took for the AFR to change when I suddenly closed the throttle. I think the problem with that approach is that by closing the throttle there is no longer much exhaust flowing and hence it's not a true sample of the delay. Quote Link to comment Share on other sites More sharing options...
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